Since the discovery that titanium can fuse to bone, titanium dental implants have represented a growing field of dental reconstruction technology for replacing natural teeth. During implantation, a hole is drilled through the gingiva, the gums surrounding the root of a tooth, and into the jawbone. An implant, which may be made, for example, of titanium or titanium alloy, is then fixed within the hole of the jawbone. Over a period of months, the implant fuses to the jawbone through a process called osseointegration, after which a permanent replacement tooth may be attached to the implant.
In many implant procedures, to form the permanent replacement tooth, a transfer coping (also referred to as an impression coping) is attached to the implant, or an abutment that attaches to the implant, to transfer the position of the implant in the patient to a working model in the dental laboratory. Once the transfer coping is attached to the implant, typically with a separate securing screw, an impression of the patient's dental structure is made using an impression material, such as, for example, polyethyl rubber or polyvinylsiloxane. The impression material, with the transfer coping embedded in the impression material, is then removed and sent to a dental laboratory, where the permanent tooth is fabricated. The position of the implant in the patient is thus identified by the position of the transfer coping within the impression material.
Many conventional transfer copings require a screw to attach the transfer coping to the implant, for example, to internal threading on an implant, while the impression is made. Two methods for making impressions are commonly used: open tray and closed tray techniques. In closed tray techniques, the transfer coping is engaged with the implant and impression material is injected around the coping. The impression is then removed, leaving the transfer coping in place. In open tray techniques, the screw is loosened and then the transfer copings are picked up with the impression material as it is removed. Conventional open and closed tray techniques both use screws to secure the transfer coping to the implant. The use of a screw makes it difficult to locate the implant through the top of the impression tray. Additionally, a conventional transfer coping that requires a screw can't be used if the patient has limitations on opening her mouth when using an open tray technique, thus necessitating retro-fitting the transfer coping back into the impression after it has been removed from the implant using a closed tray technique. This limits the accuracy of the poured stone model and/or increases the chances that the transfer coping is not properly re-oriented into the impression.
Accuracy in the identification of the location is desirable to ensure that the permanent tooth properly fits in the implant and relative to the patient's existing teeth and gumline. Failure to accurately position the permanent tooth could result in patient discomfort and/or failure of the restoration or implant. Thus, there is a long-felt need in the industry for a transfer coping that may accurately and reliably identify the position of dental implants in patients. Moreover, there is a long-felt need for a transfer coping that facilitates the impression process, requiring less manipulation by a dentist or dental technician, and that reduces the chances of having to retro-fit the transfer coping back into the impression material after removal from the implant.
Although various exemplary embodiments of the present teachings may obviate one or more of the above-mentioned problems and/or achieve one or more of the above-mentioned desirable features, it should be understood that some exemplary embodiments may not necessarily obviate one or more of those problems and/or achieve one or more of those desirable features.